The subject matter disclosed herein relates to plasma spray guns. Specifically, the subject matter disclosed herein relates to a universal plasma extension gun including at least one extension arm.
Thermal spraying is a coating method wherein powder or other feedstock material (e.g., metals, ceramics, etc.) is fed into a stream of heated gas produced by a plasmatron or by the combustion of fuel gasses, for application on a surface/machine component. The hot gas stream entrains the feedstock to which it transfers heat and momentum. The heated feedstock is further impacted onto the surface, where it adheres and solidifies, forming a thermally sprayed coating composed of thin layers or lamellae.
One common method of thermal spraying is plasma spraying. Plasma spraying is typically performed by a plasma torch or gun, which uses a plasma jet to heat or melt the feedstock before propelling it toward a desired surface. Current plasma spray guns are commonly configured to operate in a single set position with respect to a component (e.g., at a single contact distance) at one power mode (e.g., 75 kW). As a result, application of thermal spray coatings to components which include a variety of surfaces, configurations and/or different shapes (e.g., interior diameter features, outer diameter features, a plurality of varied components, etc.), may require the use of a plurality of plasma spray guns, arranged in different positions. This multitude of plasma spray guns and need for repeated spray gun substitution, configuration and calibration throughout application processes may greatly increase part production time, component expense, and maintenance equipment inventory. Additionally, some of these features (e.g., cavities, interior diameters, etc.) may be difficult to access and/or coat for technicians and robotic arms which may not be able to extend within these features. As a result, designs may be limited and/or production time may be greatly increased.